1. Field of the Invention
The present invention relates to a formation and making method of an integrated light-triggered and light-quenched static induction thyristor (hereinafter abbreviated as LTQSI thyristor) composed by integrating a light-triggered static induction thyristor (hereinafter abbreviated as LTSI thyristor) and static induction phototransistors (hereinafter abbreviated as SIPTs) or a photodarlington circuit including a light-triggered static induction thyristor and static induction phototransistors.
2. Description of the Prior Art
Formational examples of LTQSI thyristors have already been proposed by Japanese Patent Preliminary Publication Nos. Sho 60-198779 and Sho 61-54668 whereas and a making method thereof has been disclosed by Japanese Patent Preliminary Publication No. Sho 62-11470. The LTQSI thyristors proposed by these patents, however, have a drawback that the SIPT thereof has a current gain level lower than that obtainable by the SIPT operated in the normal mode since the former is operated in the inverse mode when quenched by light.